Phase Demodulator
Original Publication Date: 1965-Apr-01
Included in the Prior Art Database: 2005-Mar-06
Publishing Venue
IBM
Related People
Abstract
The circuitry demodulates phase-modulated waves with four possible phases. The method adds the modulated wave and the inverted modulated wave to a reconstructed carrier wave substantially equal in amplitude, and to the same carrier shifted by a fourth of a period, and selects the amplitude levels, drawing 1.
Phase Demodulator
The circuitry demodulates phase-modulated waves with four possible phases. The method adds the modulated wave and the inverted modulated wave to a reconstructed carrier wave substantially equal in amplitude, and to the same carrier shifted by a fourth of a period, and selects the amplitude levels, drawing 1.
A reconstructed carrier is obtained through synchronizing a circuit tuned on a frequency equal to the quadruple of the carrier frequency by the received signal, and through dividing by four the frequency of the obtained wave, drawing 2.
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